In recent times light emitting diode (LED) based lighting solutions have been developed that provide more capabilities than traditional technologies (e.g. incandescent, compact fluorescent (CFL)). These lighting solutions includes, among others, the possibility of tuning the colour temperature (e.g. from warm white to cool white) and creating a large gamut of colours. For example, the Philips Hue family of products allow for both options: temperature tuning from 2200K to 6500K and around 16 million possible colour combinations.
By enabling external systems to control light sources of a lighting system (in a secure way), it is possible to additionally use lighting in a completely new way; mainly, as a notification tool for different events. Some common implementations of this are for example the interactions between the Philips Hue system and IFTTT (If This Then That), an online service that links different systems in an event-reaction based behaviour, following the format of: “If (event X) happens, then perform (action Y)” where X and Y can be associated with different cloud-based services. A typical use case of this is to allow IFTTT to flash a specific lamp blue when a 3rd party weather forecasting service detects high probability of rain in the coming period. If a user sets this function to a light source close to their home entrance, the user gets a reminder to pick up an umbrella before leaving. Another example is to connect lamps to an external alarm system, such that when an emergency is detected (e.g. smoke in the kitchen), light sources in a user's home flash red.
For this to happen it is necessary that the lighting system (wired or wireless) has a certain level of intelligence or control, such that it can detect the presence of these triggers/events, and can transform them into relevant light settings. In the case of the Philips Hue system this is done by the Hue bridge. The Hue bridge is a small computing device in the user's home that controls the lighting system.